Hmmm, I drove a R36 in mid 2010 so i'll have a go...

* From my understanding the haldex & DSG are the same, possibly haldex set up a little differently in the R36. It is reasonable to expect that improvements could have been made in the B7...
* The B7's have 3 point udjustable suspension comfort, neutral, sport. In sport mode which also increases steering weight, it would be almost on par with the R36.
* From memory the R36 was geared a little differently but ultimately both the R36 & B7's engines are the same beast & do exactly the same thing in the go bloody great department.
* The R36 doesn't have as much sound deadening in the exhaust as the b7's do so does sound a little more visceral & louder, however the B7's engine note I have found sounds a little deeper & going through a tunnel or parked in your garage it is quite entertaining listening to it purrrrrrr or grrrrrrrr.......